#ifndef MORTAL
#define MORTAL

class Mortal
{  public:
   
   Mortal();
  
   bool is_alive();
   int  get_creation_time();
   int  get_estimated_life_duration();

   protected:
   virtual int  get_estimated_life_duration_()=0;


   private:
   
   int estimated_life_duration_;
   int creation_time_;
};






#endif